The world size had been expanded up to 80x80, almost 2 years ago.
I never felt continents were circular.

By the way, I'd like another expansion, one using the xenos and all alien life more.
I feel the planet is too swiftly like another Hearth, save few research,
we can't really chose about the future of the uniqueness of the planet:
eraze (terraform), maintain (looking for symbiosis), or exploit (slavery & pollution)...

Pangea-maps indeed feel a bit "circular" and don't differ much from how it feels to play them every time.
But Continents as well as Archipelago feels quite different everytime and none of the landmass-shapes there remind me of circles.